About the Saving Water, Saving Energy blog

The Saving Water, Saving Energy blog provides news, resources and analysis on water, energy, and climate change issues with an emphasis on the inextricable connections between water and energy, also know as the Water-Energy Nexus.

Quick Primer on Why Climate Change is Water Change and How Watershed Groups Can Get Involved

Climate change will have profound impacts on water resources in the United States. River and watershed groups can and must play a central role in addressing global warming.

Posted: 09/21/2010

Author: Bevan Griffiths-Sattenspiel

For those of you still not convinced that climate change should be a concern for river and watershed groups, here’s a quick review of what the science says, followed by a discussion of how the work you’re currently doing to protect rivers can fit into the broader effort to address climate change.

The purpose of this post is to provide a quick and dirty rationale for river and watershed groups to get engaged on climate change issues, specifically efforts to reduce greenhouse gas emissions. In a nutshell: climate change is water change and if we don’t cut back on greenhouse gas emissions, our water resources, including the people and wildlife they support, will suffer.

I also want to explain how working on climate issues doesn’t necessarily mean a complete organizational makeover. Instead, by understanding the connections between water, energy and climate change, you will see how most of the issues that river and watershed groups are already working on – such as water efficiency, low impact development and river restoration – are key strategies to addressing global warming.

First off, climate change exists and there really is a scientific consensus that carbon dioxide emissions from human activities are warming the planet. For those skeptics out there with a pocket full of arguments that appear to refute the science behind global warming, check out Skeptical Science for some clear and concise explanations of what the peer-reviewed scientific literature actually has to say.

Secondly, water will be the vector through which we experience the affects of climate change and the sooner we reduce greenhouse gas emissions, the less impact global warming will have on your watershed. In 2008, the Intergovernmental Panel on Climate Change declared, “Water and its availability and quality will be the main pressures on, and issues for, societies and the environment under climate change.” Echoing this conclusion, the June 2009 U.S. Global Change Research Program report on climate impacts - which John Holdren called “by far the most up to date, comprehensive and authoritative assessment of climate change impacts on the United States” - specifically mentions water in eight of the report’s ten key findings. A recent study comparing water demand and climate change projections in the United States has found that under a “business-as-usual” scenario, water supplies in 70% of counties in the U.S. may be at risk to climate change, with approximately one-third of U.S. counties at high or extreme risk.

While I don’t have the time to go into details, the science basically says that some areas will receive less precipitation while others will receive more. In general, weather will trend more towards the extremes, meaning that droughts will last longer and rain will come in larger, more abrupt storms. Salt water intrusion in coastal areas will become an increasing threat to groundwater as the sea level rises. Water demand may go up in the two largest water-using sectors – agriculture and electric power production – as farmers need to irrigate their crops more and quench the thirst of their livestock during drought, and power plants require more water for cooling from increasing heat waves. Ecosystems will also be disrupted as warmer temperatures alter the timing of peak stream flows and increase water temperature. Communities relying on glaciers or snowpack for their summer water supplies could be out of luck since every 1 degree Celsius temperature rise pushes the snow level up about 500 feet in elevation. For a quite a bit more detail, here’s a good summary of the effects of climate change on water resources in the U.S. (PDF) from 13 Federal agencies, including NASA, the EPA, the NSF, the Department of Commerce and the Department of Defense. You can also look at the IPCC's excellent Climate Change and Water.

While future projections of the effects of climate change are frightening, the real scary part is that global warming is already impacting our rivers and watersheds. Researchers have found that climate change is already altering the flow of rivers and that rivers in the U.S. are getting warmer, with global warming being a likely culprit. Adding to the evidence that climate change is water change, a recent EPA report on climate change indicators found, among other things, that heavy precipitation events have noticeably increased over the last 100 years, glaciers and snowpack have been shrinking since the 1960’s, sea level is rising at an accelerating pace, and from 2001 to 2009, roughly 30 to 60 percent of the U.S. land area experienced drought conditions at any given time. Look below for charts from EPA's Indicators report showing the increase in extreme precipitation events and the loss of snowpack in the Western United States:

Hopefully by now it’s clear that climate change presents the greatest long-term threat to rivers and watersheds. While the evidence tells us that watershed movement should be committed to fighting global warming, I am well aware that every single river in this country faces much more immediate threats and that it is unreasonable to expect small, underfunded river groups to begin devoting their precious time to something as big and abstract as climate change.

But what if I told you that you can protect your river from immediate threats and fight climate change at the same time? What if all it took was a little bit of reframing and messaging to connect your current work with the effort to address global warming?

Because saving water saves energy, strategies that reduce water use and protect our rivers – including water conservation, efficiency, reuse and low impact development – will reduce greenhouse gas emissions and help fight climate change. As we described in The Carbon Footprint of Water, water-related energy use in the U.S. is at least 521 million MWh a year—equivalent to 13% of the nation’s electricity consumption. The carbon footprint currently associated with moving, treating and heating water in the U.S. is at least 290 million metric tons a year, which represents 5% of all U.S. carbon emissions and is equivalent to the emissions of over 62 coal fired power plants. Water efficiency has been shown to achieve energy savings comparable to traditional energy conservation measures but at half the cost. Therefore, investing in water-oriented strategies can be a cost-effective way to reduce greenhouse gas emissions and fight climate change. Here are some examples highlighted in the report:

Outdoor water use often drives peak water demands and requires the utilization of marginal water sources with greater energy intensities. Reducing outdoor irrigation—especially during summer months—can result in substantial “upstream” energy savings by reducing water consumption from the most energy-intensive supplies and by avoiding the need to develop additional supplies.

A 5% reduction in water distribution system leakage would save 270 MGD of water and 313 million kWh of electricity annually, equal to the electricity use of over 31,000 homes. In addition, approximately 225,000 metric tons of CO2 emissions could be avoided.

If groundwater levels across the United States were to drop an average of 10 feet due to unsustainable water withdrawals, energy demands for agricultural groundwater pumping would increase by approximately 1.1 million MWh per year. Assuming pumping energy is derived from the U.S. electrical grid, associated carbon dioxide emissions would be approximately 680,000 metric tons per year.

An average sized 1,000 MWh power plant that installs a water reuse system for cooling tower blow-down recovery would reduce the energy demand to produce, distribute and treat water by a net 15%, or enough to power over 350 homes for a year.

Over the next century, climate change will dramatically alter natural resource management. Specifically, historical reference conditions may no longer serve as benchmarks for restoration, which may foster a “why bother?” attitude toward ecological restoration….Riparian ecosystems are naturally resilient, provide linear habitat connectivity, link aquatic and terrestrial ecosystems, and create thermal refugia for wildlife: all characteristics that can contribute to ecological adaptation to climate change. Because riparian systems and the projected impacts of climate change are highly variable geographically, there is a pressing need to develop a place-based understanding of climate change threats to riparian ecosystems. Restoration practitioners should consider how they can modify practices to enhance the resilience of riparian ecosystems to climate change. Such modifications may include accelerating the restoration of private lands, participating in water management decisions, and putting the emerging field of restoration genetics into practice.

I could go on and on about why the watershed movement needs to continue to be increasingly engaged in climate issues, and why rivers are so critical to adapting to global warming. But this post was supposed to be short. If nothing else, , it is time for groups already working on water efficiency, green infrastructure and riparian restoration to take some credit for all the good work you’re doing to address global warming, even if you weren’t aware of it.